In an electronic component in which an organic element or an organic material is disposed between two transparent substrates, countermeasures, for example, bonding the outer peripheral portions of the two transparent substrates with a resin sealing material and further disposing a drying agent to the inside of the electronic component, etc. have been adopted in order to protect the organic element or the organic material against moisture, water, etc. However, the resin bonding was poor at a gas barrier property (airtightness), and molecules of water were likely to permeate gradually and then the resin bonding failed to obtain a sufficient reliability. On the other hand, while a sealing material using low melting glass can provide bonding of high gas barrier property (airtightness) but the bonding temperature is remarkably higher than that of the resin sealing material and exceeds temperature for the heat resistance of the organic element or the organic material disposed in the electronic component.
Then, a laser sealing capable of local heating was devised. As the sealing material, low melting glass capable of airtight bonding is used. It is important that the low melting glass is heated and softened and fluidized by absorption of a laser light used. By using such a method, since only the outer peripheral portions of the two transparent substrates can be heated, glass bonding of high gas barrier property (airtightness) is possible without thermally damaging the organic element or the organic material disposed in the electronic component.
In devices such as a display which contains an organic light emitting diode (OLED), a glass substrate in which a sealing material is temporarily sintered to the outer peripheral portion and the other glass substrate formed with the OLED are brought into contact and a laser is applied through the glass substrate thereby softening and fluidizing the low melting glass in the sealing material to bond the two glass substrates. A sealing material is proposed in Patent Literature 1 which can be used for bonding an outer peripheral portion of an OLED display by a laser. The sealing material contains a V2O5—P2O5—Sb2O3 type low melting glass that can be heated by the laser and filler particles of lithium aluminosilicate (β-eucryptite) for lowering a heat expansion coefficient. Further, the low melting glass contains one of K2O, Fe2O3, ZnO, TiO2, Al2O3, B2O3 and WO3 and has a transition point Tg lower than 350° C. A glass package using a sealing material identical with that of Patent Literature 1 is also proposed in Patent Literature 2. The low melting glass contained in the sealing material is also identical with that of Patent Literature 1. Herein, trivalent or tetravalent vanadium ions are prevented from changing to penta-valence by temporarily sintering to the outer peripheral portion of the glass substrate in a less oxidizing atmosphere with a smaller amount of oxygen than that in air. And this process thereby prevents the softening and fluidizing property by laser irradiation from degradation and prevents the moisture resistance and water resistance at the bonded portion from deterioration after the laser sealing.